This invention is related to electrothermal propeller deicers, and more particularly, an electrothermal deicer assembly having a wiring harness and mounting hardware for use with such a propeller deicer.
The hazards of aircraft flight in atmospheric icing conditions are well known. Through the years, various workers in the art have developed various techniques for removing or preventing ice accumulation encountered during flight. Certain techniques are particularly adapted to protect specific parts of an aircraft. An electrothermal propeller deicing system is an example of a specialized system.
In an electrothermal propeller deicing system, electrothermal deicers are bonded to the inboard leading edge portions of the individual blades of an aircraft propeller. An example of an electrothermal propeller deicer is presented in U.S. Pat. No. 4,386,749 to Sweet. Electrical power is supplied to the individual deicers through flexible wire harnesses that act as jumpers between each blade and the propeller bulkhead. The harnesses must be flexible since each blade must be able to rotate about its axis in order to effectuate pitch changes. An example of a wire harness is presented in U.S. Pat. No. 5,020,741 to Ziegler et al.
Electrical power is conducted to the propeller ice protection system through a sliding contact comprising a slip ring assembly and a brush assembly. A typical arrangement is presented in U.S. Pat. No. 4,136,295, to Sweet.
It is also well known in the art that environmental issues cause various types of failures for the electrical resistance deicer heater as well as the wiring harness used to energize that heater. Because of the exposure of the deicer system to such environmental conditions as rain, sand, dust, birds, extreme temperatures, etc., it is essential that the deicer be easily replaceable while being firmly secured in a facile manner to the propeller blade assembly in order for the blade to rotate about its axis. One attempt to improve a propeller deicer wiring harness system is disclosed in U.S. Pat. No. 5,174,717 to Moore.
Efforts regarding such deicer systems have led to continuing developments to improve their versatility, practicality and efficiency.
It is a primary of the present invention to provide a low cost, durable, and easily installed wiring harness and connection system for use with aircraft propeller electrical resistance deicer units.
It is also an object of the present invention to provide a harness assembly which significantly reduces the amount of time required for the removal of an old deicer unit and installation of a new deicer unit while at the same time reducing the level of skill required for the installer.
It is further and object of the present invention to minimize the requirement for parts and pieces for the assembly, such as nuts, bolts, cable clamps and the like which increase the costs and time required for the assembly.
It is still further an object of the present invention to provide an electrical propeller deicer assembly which has common parts for utilization on propellers for blade revolution in either the clockwise or counterclockwise engine drive direction.
To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings.
According to the present invention, a system for electrically connecting deicer leads extending from an electrical resistance heater propeller blade deicer to source leads connected to an electrical power source, the propeller being mounted on a hub, the system having: (a) a first connector having separate electrical terminals for each of the deicer leads;(b) a second connector having separate electrical terminals for each of the source leads, wherein the first and second connectors are mated together to form a mated connection to provide electrical power to the deicer;(c) a support bracket having: a tongue for attachment to the hub; projections configured to define a carriage portion for receiving the mated connection and limiting movement thereof; and an aperture provided in the support bracket; and, (d) a first flexible strap having an adjustable, tightening, locking mechanism, wherein the flexible strap is inserted through the aperture, around the mated connection, tightened and locked to secure the mated connection in position on the hub relative to the deicer, the flexible strap being removable to permit disassembly of the connector members and to permit replacement of the deicer or deicer source leads.
The present invention provides an easily replaceable connect system which is retrofitable to existing electrical heater deicers, is inexpensive and reduces electrical heater replacement times by a significant amount. It allows simplified installation and removal of system and eliminates the need to disengage brackets when servicing the deicer heating element or wire harness. The new bracket also allows for multi-positioning of the propeller blade balance weights and allows for usage of a single deicer and hardware assembly for utilization on propellers which revolve in either the clockwise or counterclockwise direction.